Lightroom Noise Reduction Tutorial

Lightroom is a wonderful image processing program for beginners to advanced professionals alike. It’s user interface is can be configured for all levels of users. Lightroom excels in indexing and organizing your images and making them searchable, and Lightroom is a very competent RAW image processor. With a powerful print module, web interface, and slideshow capabilities its perhaps one of the most complete image programs available. I use it, most pros I know use it, and if sales are any indication more photographers use Lightroom than any other imaging program.

Adobe improved the noise reduction capabilities dramatically in v3 and I’m sure they’ll get better and better in future versions. In Lightroom you have the choice of using aftermarket plug-ins or their own excellent noise removal engine.

Nik Dfine is one such plug-in which I highly recommend. Nik Software makes quality products which work well in both Adobe Photoshop Lightroom, and Adobe Photoshop CS5.

Most modern digital cameras don’t show significant noise from ISO 100-800, in general the bigger the sensor the less visible noise. So let’s take a look at an ISO 1600 image which exhibits heavy noise which could benefit from noise reduction. This is a 1:1 crop which easily shows the noise, a full size image at this size would show much less noise, but when you zoom in for a closer look this is what you get.

Notice the heavy noise against the dark background? Anything we do other than white balance adjustments will increase the overall noise of this image. Fortunately the exposure was spot on when captured, but let’s take a look at what happens when we apply a reasonable amount of sharpening.

Notice the heavy increase in noise? Look at the face of the closest subject and compare it to the example above this one. If we’d have to have increased exposure the noise would have been much worse.

There are two main types of noise. Color noise, and luminance noise. Noise in a digital image looks very much like ‘grain’ in a film image, but not nearly as neat or uniform. Digital noise is more splotchy and much less attractive. Color noise appears as a bunch of colorful speckles mostly visible in the dark parts of the image, while luminance noise is visible throughout the entire image and looks a lot like film grain. Lightroom has slider controls for both types of noise.

This image is exhibiting luminance noise. Luminance noise breaks up fine detail. As you apply noise reduction fine detail ‘blends’ giving the effect of a softer image. You’ll only want to apply ‘just enough’ noise reduction to make the noise level acceptable at the size you wish to view the image. Too much noise reduction will make a terribly soft image, not enough and it’s too noisy. Let’s look at some examples.

Looking at the above image and comparing it to the original above you can see it looks very soft. The three controls for luminance noise Luminance (overall level of reduction), Detail (the size of the small area of the image it works with), and Contrast (adjusts the contrast between the small areas being adjusted)..

As you can see 100% of luminance noise reduction with the detail at 2 eliminates the visible noise, but takes away significant detail leaving a soft image.

Here, we left the detail at its default of 50, and slid the Luminance slider to the right from its default of 0 to where most of the noise is gone at 42. Not all of the noise is gone, but the image is much more acceptable without sacrificing too much detail. This is what we want, a nice balance between overall reduction of noise, and overall detail present in the image.

To further help the ‘look’ of noise be reduced we can increase the contrast by adjusting the black level from its default level of 5, to the 12 shown above.

As you can see, there are many factors which affect noise. The size of your cameras sensor, how far from the captured exposure level you need to adjust for, how much sharpening is applied, and then how much noise reduction is applied to clean it all up. We balance noise reduction with apparent detail, and contrast adjustment can help reduce the apparent ‘look’ of noise.

If you’re shooting in difficult conditions, like the concert in the example above, you’ll want to be sure to get the proper exposure right out of the camera. You then want to make the least exposure and image corrections as possible, add just enough sharpening as needed, but not too much, and then apply your noise reduction ‘just enough’ to make the noise level acceptable while retaining as much detail as possible.

That’s it. It’s not a complicated process.

Will noise removal plug-ins do a better job of noise reduction? Yes, often they will. Depending on the image and the circumstances of capture, this difference may be very slight, or significantly different. The noise reduction capabilities built into Lightroom are very good, but you would probably benefit from a quality noise reduction plug-in like Nik Dfine, Neat Image, or Noise Ninja.